When performing diagnostic, therapeutic or interventional vascular procedures involving a catheter, it is necessary to flush the catheter (typically with saline) in order to prevent blood clots from forming. The device most commonly used today is a manifold with a number of manually operated stopcock valves. Periodically the physician or technician must manually open or close one or more stopcocks for a period of time so that saline from a high pressure source can flush the catheter. After a satisfactory amount of flushing has been done, the stopcocks are again manually moved back to their original position, and the surgeon then resumes performing the procedure.
There are a number of shortcomings with the existing manifold. One is that the physician is "hands off" from performing the procedure for a long period of time (20 seconds or more per flush), which time could instead be used to perform the procedure on the patient. Having to manually flush also breaks the continuity of the procedure, which can be distracting. It also requires that the operator (if not the physician) is at all times sterile. Another shortcoming is that flushing must be done fairly often. During each flush, blood pressure readings are interrupted, which is undesirable. Each additional flush is also another interruption, potential distraction and further delay of the procedure.
What has been needed is an apparatus for flushing a vascular catheter which automatically closes and which provides a relatively slow continuous flush of the catheter.